Modification of lithium manganese oxide cathode material cycling performance for new energy vehicle lithium-ion battery
YU Jingbin1，LIANG Weiqiang2
（1.College of Automotive Engineering, Shanxi Vocational University of Engineering Science and technology, Jin‐
zhong 030619； 12. College of Mechanical Engineering，Taiyuan University of science and technology, Taiyuan
030024）
Abstract：Among the current mainstream lithium-ion cathode materials, spinel lithium manganese oxide
(LiMn2O4) has been widely applied in mini-type new energy vehicles due to its advantages of low cost and high
safety. At present, the main obstacle for the development and application of lithium manganate cathode materials is
manganese dissolution. The dissolution of manganese will lead to a rapid deterioration of cycle performance, espe‐
cially in high temperature cycles. In this study, lithium fluoride was used as the coating material to be coated on the
surface of lithium manganate oxide cathode material, in order to isolate the lithium manganate oxide from the elec‐
trolyte and inhibit the dissolution of manganese. X-ray diffraction shows that there is no fluorine doping in the cosintering process of lithium fluoride and lithium manganate oxide. Hence, there is no structural change of lithium
manganate oxide. The optimum lithium fluoride coating amount is determined by studying the electrochemical im‐
pedance spectroscopy of different lithium fluoride coating amount. Compared with the original lithium manganate
oxide, the lithium manganate oxide that is coated with lithium fluoride shows better electrochemical performances. Among them, the energy density of the pouch battery is 183 Wh/Kg, and the room/high temperature capacity reten‐
tion after 1 000 cycles are 90.3% and 75.7 %.
2023, Vol. 33 
